Fluid cooled damper



0d.' 29, 194e. D; DAMN` 2,410,017 1 FLUID GOOLED DAMPER vFiled Aug. 14, 1945 2 sheets-sheet 1 j: .3 @il Patented Oct. 29, 1946 FLUID COOLED DAMPER David Dalin, Sodertalje, Sweden Application August 14, 1943, Serial No. 498,697 In Sweden September 16, 1941 Claims.

This invention relates to heat exchange apparatus and refers particularly to steam generating plants equipped with superheaters.

In equipment of this type it is desirable that the steam be maintained at a predetermined temperature regardless of the demands upon the plant and possibly varying furnace conditions.

This is done, as it has been to some degree in the past, by locating the 'superheater in one of two parallel but separate gas passes or passageways connected between a source of hot gases and a receiving gas pass and controlling the flow of hot gases through the two passes. vThus the effect of the hot gases upon the superheater located in one of the parallel gas passes and another heat exchanger located in the other gas pass or passes may be varied as required to maintain the superheated steam at a predetermined temperature regardless of variations in quantity and pressure of the steam, it being understood that the hot gases which are not required to maintain the desired temperature of the superheated steam flow through the other gas pass in which the other heat exchanger is located without lowering the overall heat exchange eiciency of the combined unit.

While attempts have been made in the past to control the flow of hot gases in a steam boiler by means of dampers, these past expedients were objectionable in that the damper means they employed were incapable of withstanding the extreme temperatures prevalent in equipment of this character.

It is, therefore, another object of this invention to provide an improved manner of providing a dampercr shutter construction for controlling the ow of gases through a gas pass which is so designed as to be duid cooled and thereby capable of withstanding excessively high temperatures.

A further object of this invention is to provide a damperl construction for controlling the flow through a gas pass of a boiler or other heat exchange apparatus which comprises a multiplicity of iiuid cooled tubes so arranged in the gas pass that movement thereof with respect to each other may be readily affected by control instrumentalities on the exterior of the gas pass while the apparatus is in service. A

Another object of this invention is to pro- Vide an adjustable damper for controlling the flow through a gas pass which comprises a bank of fluid cooled tubes 'so` mounted so that at least some of the Itubes may be flexed to alter their positions with respect to adjacent tubes and thus control the flow of gases through the pass.

Still another object of this invention is to provide an adjustable damper of the character described which lends itself readily to the control of a plurality of adjacent though 'separate passageways.

A further object of this invention is to provide an adjustable barrier of the character described composed of a plurality of adjacent fluid cooled tubes so mounted and arranged that adjacent tubes may be readily flexed in opposite directions to thereby accomplish substantially uniform spacing between the tubes throughout their entire length so that gas flow through the damper is uniformly distributed over the entire area of the damper.

Another important object of this inventionis to utilize the adjustable barriers, or more specifically the bankof tubes constituting the barriers, as part of the heat exchanger unit in such a way that these banks of tubes serve the dual purpose of providing an adjustable barrier and part of the heat exchanger surface of the entire unit to thereby reduce the size and weight of the unit.

With the above and other objects in View which will appear as the description proceeds, this invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described and more particularly dened by the appended claims, it being understood that such changes in the preoise embodiment of the hereindisclosedv invention may be made as come within the scope of the claims.

The accompanying drawings illustrate two complete examples of the physical embodiment of the invention constructed in accordance with the best modes so far devised for the practical application of the principles thereof, and in which:

Figure l is a vertical sectional view through a portion of a steam generating plant embodying this invention, said view being taken on the plane of the line l-I of Figure 2; A

Figure 2 is a horizontal sectional View taken on the plane of the line 2--2 in Figure l;

Figure 3 is a fragmentary detail view taken `on the plane of `the line 3-3 in Figure 1;

Figure 4 is a View diagrammatically illustrating the adjustable damper or shutter in its open position;

Figure 5 is a View similar to Figure 4 but showing the adjustable damper or 'shutter closed; and

Figure 6 is a view similar to Figure l illustrating a slightly modified arrangement of the tubes comprising the adjustable damper or shutter.

Referring now particularly to the accompanying drawings in which like numerals indicate like parts, the numeral designates a gas pass oi a steam generating plant or other heat exchange apparatus, deiined by xed walls E, l, 8, Q, and I0. While the specific shape of the gas pass has no bearing upon the invention, it may be right angular, as shown, with its horizontal portion into .which the hot combusti-on gases are fed from the heat source, not shown, divided into two chambers or passages I I and I2 by a vertical wal1 I3. Both chambers have communication with the vertical outlet portion 5' of the gas pass and thus are connected in parallel between the source of hot gases and the outlet portion 5'. Flow through these parallel paths is controlled by an adjustable damper Ill which extends across the full width of the gas pass, i. e., across both 4of the two parallel chambers or passages II and vI2 and constitutes the chief feature of this invention. That section of the damper I 4, which separates the chamber o-r passage II from the outlet porti-on of the gas pass and `which is designated I4', is adapted to be controlled separately from its remaining section itl, which controls the flow through the chamber or passage I2.

The vertical wall I3 which separates the chambers II and I2 may be a bank of fluid cooled tubes, or, as shown in Figure '7, it may be part of the brick work of the boiler.

The chamber I2 has a heat exchanger I5 mounted therein which may be the superheater of the boiler and the chamber II has a heat exchanger I6 mounted therein which may constitute another steam superheater or provide means for heating some other fluid medium. The coils of the heat exchanger I5 are connected with a distributing header I'I and `a collecting header I8, the former being connected to a steam dome I9 through suitable connections, not shown.l

The heat exchanger I6 has its coils connected toa distributing header 2G and a collecting header 2I. Suitable means, not shown, connect the headers 2D and 2I in the circuit through which the fluid medium to be heated by the exchanger I6 flows. The specific manner in which the heat exchangers I5 and I8 are connected in their respective circuits, however, does not constitute any part of this invention.

The adjustable damper or shutter indicated generally by the numeral 'It may take severaldifferent forms as shown in the drawings. In that embodiment of the invention illustrated in Figures l and 2 it comprises a bank or wall of fluid cooled tubes which collectively forms a barrier extending entirely across the gas pass to throttle the ow of gases through both its chambers or passages II and I2 with an effectiveness depending upon the spacing between the adjacent tubes.

In fully closed condition, illustrated in Figure 5, the tubes occupy substantially a common plane and lie `closely adjacent to each other. In addition to being divided into the two sections id and Ill all of the tubes are arranged in at least two groups and, if desired, three groups as shown in Figure 6. In any event the tubes are so arranged and mounted that they may be displaced with respect to each other to increase and decrease the spacing therebetween and thus regulate the iloW of Vgases through the two chambers or passages of the gas pass.

It is, of course, obvious that-by so regulating the flow of gases through the gas pass the effect thereof on the heat exchangers I5 and i6 is proportionately varied.

Where the tubes are divided into two groups as shown in Figure 4 the tubes of one group designated Ilia have their upper ends free and their lower end portions xed as at 22, while the tubes Mb constituting the other group have their lower ends free and their upper ends fixed as at 23. Thus, the spacing between adjacent tubes of the two groups may be varied substantially uniformly for their entire length by simultaneously flexing the tubes of the two groups in opposite directions. In this manner gas flow through the barrier is substantially uniform over its entire All of the tubes of the adjustablebarrier are supplied with a water-steam emulsion from a distributing header 2`into which the watersteam emulsion is forced by a pump` 25. The inlet of the pump is connected to the steam dome I9 by a line 26 and the outlet thereof is connect,- ed by line 2l with the distributing header 24.

As shown in Figure 3 the tubes oi the two groups are disposed alternately in pairs with each pair constituting a loop. Thus each pair of tubes constituting the a group (those which have their upper ends free) have one end connected to the distributing header ZIIy as at 28. From this point of connection to the distributing header the coil extends down into the gas pass and then follows the ceiling Iwall 6 thereof to a point adjacent to the wall I9. Here the coil continues down along the end wall lil at a point beneath the bottom of thehorizontal stretch of the ga's pass to enter the outlet portion of the pass where the coil is doubled back and forth serpentine fashion to extend across the outlet portion lof the gas pass and be secured as at 22 tothe adjacent; wall thereof.

From this point the coil continues to form one of the pair of tubes being considered-extending upwardly to a point near the ceiling of the gas pass and then horizontally toward and into an opening 29 in the end wall Iii. rihe portion of the coil within the opening 29 is looped back on itself at 30 (see Figure 3) and doubling back on itself follows right along the path just traced so as to provide the second oi the pair of tubes (Ida) being considered. This end portion of the coil follows along behind the end portion connected to the distributing header 24 but before reaching the 'same branches off to an outlet line '3l into the lower portion of `the Ysteam dome or as alternate outlet line `t2 into the upper portion ofthe steam dome. .Y

The tubes of the b group are similarly arranged in pairs consisting of looped coils and similarly fed from the distributing header 24.

For this purpose one leg of each coil loop comprising the b group is connected tothe distributing header and then extends down thro-ugh the ceiling 6 where it is anchored as at 23. FromV this point it continues down substantially in the plane oi' the a group to a point adjacent to the bottom of the horizontal stretch of the gas pass where it is bent to extend horizontally across the outlet of theY gas pass and enter an opening or cavity 33 in the end wall Iii similar to the opening 29.

Within this openingl 33 the coil is doubled back on itself in the same way as the looped portion 30 to follow the previously traced path back across the outlet of the-gas pass and vertically across the horizontal portion of the gas pass to again enter the ceiling 6 and through discharge line 34 or its alternate discharge `line 35. connect with the steam dome.

The looped ends of the coils received in the openings 29 are connected by links 36 with bell crank levers 3l, while the loops of the coils received in the openings 33 are connected by links 38 with bell crank levers 39. The projection of the looped ends of the coils into the wall I more or less insulates the links 36 and 38 from the direct influence of hot gases owing within the gas pass.

The bell crank levers 31 and 39 are fixed to crosS shafts 3l and 39' suitably journalled on the exterior of the wall lll. These cross shafts are adapted to be simultaneously rocked by an eccentric 40 connected to both sets of bell crank levers by a link 4i. 43 fixed to the exterior of the end Wall I drives the eccentric. It is, of course, to be understood that a separate set of bell crank levers with their connections to the loops of the tubes and their driving motor is provided for each section of tubes I4' and I4". This enables separate control of the gases fiowing through the chambers or passages ll and I2 to the end thatdiminution of flow through one chamber or passage may be accompanied by an increased flow through the other and vice versa. The motors 42 (only one of which is shown) are adapted to be controlled by impulses derived from controlling instrumentalities, not shown, which in `turn are regulated by the temperature of the superheated steam or any other suitable control factor so that the adjustable damper or shutter sections I4 and I4 govern the flow of gases through the chambers or passages ll and l2 of the gas pass to maintain a predetermined steam temperature or any other factor affected by the flow of gases through the gas pass.

It is to be observed that the bell crank levers 3l and 39 are mounted in opposition so that their simultaneous actuation by the eccentric pulls on one of the links 36-38 and pushes on the other. Thus, the free ends of the tubes constituting the adjustable barrier are simultaneously flexed in opposite directions as indicated in Figure 1.

Where the tubes constituting the separate sections Ii and I4 of the adjustable damper are divided into three groups as shown in Figure 6 the pairs of tubes constituting the a and b groups have pairs of stationary tubes 44 interposed therebetween. In other respects the situation is the same as that described.

The tubes of the a and b groups may be disposed alternately instead of in pairs as shown, but in any event, the tubes constituting the ad- .'ustable damper or shutter are always xed at one end and free at the the other unless they constitute fixed tubes as in Figure 5, and to insure a substantially uniform distribution of gas now through the entire area of the adjustable damper or shutter the flexure of the tubes of the two groups takes place simultaneously and in opposite directions.

The vertical displacement of the horizontal runs of the coils where they cross the outlet portion of the gas pass permits free passage of the gases.

From the foregoing description taken in connection with the accompanying drawings, it will be readily apparent to those skilled in this art A motor 42 mounted on a bracket 6 that this invention provides an efficient and practical manner of controlling the now of gases through a gas pass in a steam boiler or other similar heat exchange apparatus. What I claim as my invention is: i

1. In a uid heat exchange apparatus: xed walls defining a gas pass; a gaseous uid heater positioned to be infiuenced by the flow of gases through said pass; a damper for controlling the flow of gases through said pass comprising a plurality of tubes arranged side by side to form a barrier of variable effectiveness depending upon the spacing of the tubes; means for circulating a cooling fluid through said tubes; certain of said tubes being laterally movable with respect to others while the apparatus is in service to change the spacing between tubes and thus vary the effectiveness of the barrier so that more or less gas ows through the gas pass to inuence the gaseous fluid heater; and means for so moving said tubes from the exterior of the gas pass. l

2. In a heat exchange apparatus: xedwalls defining a gas pass; a gaseous fluid heater positioned to be influenced by gases flowing through the pass; a bank of fluid cooled tubes connected to a source of cooling fluid and extending across said pass to form a barrier of variable eiectiveness depending upon the spacing of said tubes; certain of the tubes having portions extending from the ends thereof along the adjacent wall of the pass to a point adjacent to another Wall of the pass, said tubes being adapted to be flexed to shift their positions relative to the remaining tubes by an endwise force applied on their extended end portions; and means connected to said extended end portions and accessible on the exterior of said last named wall and through which endwise force may be applied to said extended end portions to ex said indicated tubes and vary the effectiveness of the barrier to thereby control the flow of gases through the pass and consequently regulate the extent to which the gases iniiuence the gaseous fluid heater. l

3. In a heat exchange apparatus: cooperating xed walls defining a gas pass; a gaseous fluid heater positioned to be influenced by gases iiowing through said pass; a bank of fluid cooled tubes connected to a source of cooling fluid and extending substantially entirely across the pass to form a barrier of an effectiveness depending upon the spacing of the tubes so that by regulating the spacing of the tubes the fiow of gases through the gas pass and the influence thereof upon the gaseous fluid heater may be controlled; certain of 55 said tubes having one end thereof fixed and the other end free to permit fiexure of said tubes to change the spacing between them and adjacent tubes; fluid cooled motion transmitting means connected tothe free ends of said tubes; and 60 control means on the exterior of the gas pass and connected to said fluid cooled motion transmitting means at a point spaced from the direct influence of the gases iiowing through said pass, for fiexing said tubes to change their positions 65 with relation to` adjacent tubes and thereby vary the effectiveness of the barrier. 4. In a heat exchange apparatus: cooperating fixed walls defining a gas pass; a gaseous fluid heater positioned to be influenced by the flow 70 of gases through said pass; an adjustable damper for said gas pass to regulate the effect of the gases flowing through the gas pass upon the gaseous fluid heater by controlling the flow of gases through the gas pass, ,said adjustable damper 75 comprising a bank of fluid cooled tubes forming a barrier across the pass ofan effectiveness depending upon the spacing of the tubes, said tubes each having one end xed and theother end free and being divided into at least two rgroups with the xed ends of the tubes of one group adjacent to the free ends of the tubes of the other group so that simultaneous flexure of the free ends f all of said tubes in opposite directions effects substantially uniform variation in the spacing of the tubes for their entire lengths; and means connected to the free ends of the tubes for flexing the tubes.

5. In a heat exchange apparatus: cooperating walls defining a gas pass; a gaseous fluid heater positioned to be influenced by gases flowing through said pass; means forming an adjustable damper for said gas pass and comprising a bank of` fluid cooled tubes connected with av source of Y cooling fluid and collectively constituting a barrier across the gas pass; certain cf said tubes being free at one end so as to enable flexing of said tubes to alter the spacing between the tubes and effect adjustment'of the damper; and means passing through a Wall of the gas pass and connected to the free ends of the tubes for flexing said tubes.

6. In a heat exchange apparatus: cooperating walls defining a gas pass; a gaseous fluid heater positioned to be influenced by gases flowing through said gas pass; a bank of uid cooled tubes connected to a source of cooling fluid and extending across the gas pass to form a barrier of an effectiveness depending upon the spacing of saidy tubes, adjustment of the spacing between said tubes regulating the flow of gases through the gas pass to thus control the extent to which the gaseous fluid heater is influenced by the gases; certain of the tubes having free ends to enable flexing of said tubes with relation to adjacent tubes to vary the spacing of the tubes; coil loops extending from and connected to the free ends of pairs of said tubes, said coil loops' projecting into cavities in a wall of the gas pass to have their looped portions removed from the direct influence of the gases flowing through the pass; and means on the exterior of the gas pass and connected to the looped portions for moving said coil loops in and out to flex the tubes connected thereto.

7. In a heat exchange apparatus: cooperating o walls defining'a gas pass; a heat exchanger positioned to be influenced by the flow of gases through the gas pass; a bank of fluid cooled tubes collectively constituting a barrier across the gas pass of an effectiveness depending upon the spacing of the tubes; certain ofsaid tubes having their ends at one side of the gas pass free and other tubes having their ends at the opposite side of the gas pass free so that an opposite flexing force applied on said free ends of the tubes results in varying the spacing between the tubes substantially uniformly for their entire length; looped coils connected to pairs of adjacent free ends of said tubes and extending substantially at right angles to said bank of tubes, the loops of said looped coils entering cavities in an adjacent wall tively constituting a barrier acrossA the gas pass of an effectiveness depending upon the spacing of the tubes, certain of said tubes having their ends at one side of the gas pass free and other tubes having their ends at the opposite side ofthe gas .pass free sothat opposite flexing forces applied on said free ends of theY tubes results in varying the spacing between the tubes substantially uniformly for their entire length;`looped coils connected to pairs of adjacent free :nds of said tubes and extending substantially at right angles toA said bank of tubes; and means con` nected to said looped coils for simultaneously applying opposite forces thereon to flex the tubes connected thereto in opposite directions.

of said passages to be influenced by the gases 9. In a heat exchange apparatus, xed walls defining a plurality of passages connected in parallel between a source `of heated gases and a receiving gas pass; a gaseous fluid heater in each flowing therethrough to the receiving gas pass; an adjustable damper for eachI of said passages, said dampers comprising banks of fluid cooled tubes with each bank of tubes collectively forming a barrier across its respective passage; means `for circulating cooling fluid through said tubes; and means for moving the tubes to vary the effectiveness of the barriers and thereby control the proportion of hot gases flowing through each vof the passages to the receiving gas pass and likewise control the extent to which the gaseous rfluid heaters are influenced by thehot gases.

l0. In a heat exchange apparatus, fixed walls defining a plurality of passages connected in parallel between a source of heated gases and areceiving gas pass; a gaseous fluid heater in each of said passages to be influenced by the gases flowing therethrough to thereceiving gas pass; an adjustable damper for each of said passages, said dampers comprising banks of fluid cooled tubes with each bank of tubes'collectively forming a barrier across its respective passage; means for circulating cooling fluid through said tubes; certain of the tubes of each bank of tubes being free at one end so as to enableV flexing of said tubes to alter the spacing between the tubes of each bank and effect adjustment of the dampers; and means connected to the free ends of the tubes for flexing the same to vary the effectiveness of the barriers and thereby control the proportion of gases flowing through each vof the passages to the receiving gas pass and likewise control the extent to which the gaseous fluid heaters are influenced by the hot gases.

DAVID DALIN. 

